1. Field of the Invention
The present invention relates to a hydraulic buffer of the type in which the damping force can be controlled. More particularly, the present invention pertains to improvement of the hydraulic buffer of the type described above in which an actuator for controlling the damping force can readily be mounted on a bracket secured to the projecting end of the piston rod of the buffer in a single and simple operation.
2. Description of the Related Art
A typical conventional hydraulic buffer of the type in which the damping force can be controlled comprises: a piston rod one end of which projects from a cylinder; a cylindrical bracket with a closed end which is screwed onto the projecting end of the piston rod by means of a nut in such a manner that the bracket is secured to the upper surface of a cushion member; and an actuator for controlling the damping force which is secured to the open end side of the bracket by screws through a plate (see, e.g., the specification of Japanese Utility Model Laid-Open No. 110212/1984).
In the above-described prior art arrangement, as shown in FIG. 3, a projecting end 1A of a piston rod 1 is inserted into a hole 2A of a body 2, the projecting end 1A is passed through a cushion member 3 and a bracket 5 of an actuator 4 for controlling damping force, and a nut 6 is screwed onto the projecting end 1A such as to fix the piston rod 1 to the body 2 of a vehicle, the actuator 4 also being fixed by screws 7 to the bracket 5 which has been fixed in this manner.
However, since the bracket 5 in the prior art arrangement is formed in a cylindrical shape having a bottom and the nut 6 is screwed onto the projecting end 1A of the piston 1 which projects into the bracket 5 through a hole 5A in the bottom of the bracket 5, the screwing of the nut 6 is comparatively difficult because the screwing tool needs to be inserted into the bracket 5 downwardly and the nut 6 then needs to be rotated by the tool. Furthermore, when the hydraulic buffer body is exchanged, the screws 7 are removed, the actuator 4 for controlling damping force is removed, and then the screwing tool is inserted into the bracket 5 for removal of the nut 6. The mounting and removal of the actuator 4 and the nut 6 are thus disadvantageously tiresome, involving lowered operational efficiency.